existence ends during fully formed stage anatomical system renal system AAO:0010257 An anatomical system which consists of organs and tissues which produce, store, and excrete urine.[AAO] BILA:0000015 BTO:0001244 BTO:0003092 CALOHA:TS-1323 EFO:0000803 EHDAA2:0001601 EHDAA:5901 EMAPA:17366 EV:0100095 Evolution of vertebrate renal anatomy appears quite conservative when compared, for example, to evolution of respiratory and cardiovascular systems in vertebrates. Major anatomical changes in vertebrates kidneys separate those of birds and mammals from kidneys of lower vertebrates. General increase in animal size from fish to mammals is reflected by an increase in total number of nephrons per kidney, rather than by constant change in tubular dimensions.[well established][VHOG] FBbt:00005056 FMA:7159 GAID:391 In humans, the renal system comprises a pair of kidneys, a pair of ureters, urinary bladder, urethra, sphincter muscle and associated blood vessels In various sources such as Encyclopedia Britannica, the excretory and urinary systems are indeed the same system (see wikipedia talk page); we merge two BTO classes here MA:0000325 MAT:0000027 MESH:D014551 MIAA:0000027 TADS:0000162 TAO:0000163 The renal system in an anatomical system that maintains fluid balance and contributes to electrolyte balance, acid/base balance, and disposal of nitrogenous waste products.. This definition is inclusive of the organs of the vertebrate renal system, as well as the Malpighian tubules of insects, and allows for future incorporation of structures such as the antennal glands of crustaceans UBERON:0001008 UMLS:C1508753 VHOG:0000723 WBbt:0005736 XAO:0000143 ZFA:0000163 excretory system galen:UrinaryTract renal or urinary system renal system renal/urinary system systema urinaria systema urinarium uberon urinary system urinary tract